I just don't see how it is "abuse" to use a product as sold (and this was no secret), and to give an airline, say, $1700 to $2000 for 2 tickets when they would be much more likely to go to an upgrader or a mileage redeemer if they don't sell all the seats.
This airline has done nothing to discourage or prevent card churning and multiple cards, including multiple bonuses, and multiple companion fares. They have had years to do so. Sorry, not abuse. The credit card partnerships are way too valuable.